U.S. patent number 6,654,662 [Application Number 09/355,463] was granted by the patent office on 2003-11-25 for method for organizing the storage of different units.
This patent grant is currently assigned to Autostore AS. Invention is credited to Ingvar Hognaland.
United States Patent |
6,654,662 |
Hognaland |
November 25, 2003 |
Method for organizing the storage of different units
Abstract
The invention concerns a method for organising the flow of goods
for a stock consisting of heterogeneous units arranged closely on
top of and beside one another in stacked standardised
parallelepiped-shaped containers (1) which are joined into several
co-ordinate-forming layers of containers in a vertical framework
(6). With one or more computer-controlled lifting devices (5) with
a gripping device (3) each individual container is lifted
mechanically up and out of the stack for manual replenishment or a
manual packing station (7). After dispatch the container (1) is
returned to a new random, but continuously known position. The
random and continuous alteration of location compels the
statistically most frequently sold goods to be located in
containers which have recently been returned to the upper layer of
the stack, while those goods which statistically are seldom sold
over a period of time will be located in containers in the lower
layers of the stack.
Inventors: |
Hognaland; Ingvar (Nedre Vats,
NO) |
Assignee: |
Autostore AS
(NO)
|
Family
ID: |
19900681 |
Appl.
No.: |
09/355,463 |
Filed: |
July 29, 1999 |
PCT
Filed: |
April 30, 1998 |
PCT No.: |
PCT/NO98/00136 |
PCT
Pub. No.: |
WO98/49075 |
PCT
Pub. Date: |
November 05, 1998 |
Foreign Application Priority Data
Current U.S.
Class: |
700/214; 700/216;
700/217; 700/228 |
Current CPC
Class: |
B65G
1/1371 (20130101); B65G 1/0464 (20130101) |
Current International
Class: |
B65G
1/137 (20060101); G06F 007/00 () |
Field of
Search: |
;700/230,228,227,215,216,217,218,281 ;414/933,796.9,792,796.2 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
2629718 |
|
Jan 1978 |
|
DE |
|
4133218 |
|
Apr 1993 |
|
DE |
|
0217757 |
|
Apr 1987 |
|
EP |
|
0767113 |
|
Apr 1997 |
|
EP |
|
163276 |
|
Feb 1986 |
|
NO |
|
Primary Examiner: Walsh; Donald P.
Assistant Examiner: Butler; Michael E.
Attorney, Agent or Firm: Patterson, Thuente, Skaar &
Christensen, P.A.
Claims
What is claimed is:
1. A system of organization with respect to location and flow of
goods for a stock of heterogeneous units in a store having a
plurality of stacks of standardized containers, comprising: a
vertical framework to store a plurality of stacks of standardized
containers, wherein the framework is accessible from the top; a
plurality of standardized parallelepiped-shaped containers having
four outer vertical sides and adapted to the physical dimensions of
the units for storing the units therein, the containers being
arranged in horizontal layers and deep-stacked and stock joined in
the vertical framework, thereby forming several horizontal
co-ordinate forming layers of containers whose positions at any
time are random; a computer system to continuously monitor and
record the positions of the containers; at least one lifting device
including a gripping device, wherein the lifting device has access
to the framework from the top of the framework, wherein a lifting
device is moved to a position above a stack having the same
horizontal co-ordinate as the horizontal co-ordinate recorded in
the computer system for a desired container; wherein the lifting
device is used to grip and hoist a top most container from the
stack, wherein the top most container that is not the desired
container is moved to a temporary position, wherein the lifting
device continues to move containers from the stack to temporary
positions until the gripping device grips the desired container,
wherein the lifting device is used to move the desired container to
a predetermined location, wherein the containers moved to temporary
positions are returned back to the stack so that their relative
order is retained, and wherein the desired container is returned to
a top of a stack; whereby to minimize retrieval and delivery time
of desired containers between the store and the predetermined
location, requests for containers from the store during a given
period of time are input together into the computer system so that
prior to the given period, the containers in each stack are
arranged so that a container to be retrieved more frequently than
another container during the given period is placed higher in each
respective stack.
2. The system according to claim 1, wherein the containers are
divided into different compartments according to their purpose.
3. The system according to claim 1, wherein the at least one
gripping device is constructed and arranged in the form of a board
with gripping fingers, and wherein each container has corresponding
grooves arranged for being gripped by the gripping fingers, so that
when the gripping device engages a container, the board forms a lid
over the container.
4. The system according to claim 1, wherein outer vertical sides of
the containers have slide-forming vertical grooves to control
movement and reduce friction and surface contact against the
vertical framework when the containers are moved vertically within
the framework.
5. A system of organization with respect to location and flow of
goods for a stock of heterogeneous units in a store having a
plurality of stacks of standardized containers, comprising: a
vertical framework to store a plurality of stacks of standardized
containers, wherein the framework is accessible from the top; a
plurality of standardized parallelepiped-shaped containers having
four outer vertical sides an adapted to the physical dimensions of
the units for storing the units therein, the containers being
arranged in horizontal layers and deep-stacked and stock joined in
the vertical framework, thereby forming several horizontal
co-ordinate forming layers of containers whose positions at any
time are random; a computer system to continuously monitor and
record the positions of the containers; at least one lifting device
including a gripping device, wherein the lifting device has access
to the framework from the top of the framework, wherein a lifting
device is moved to a position above a stack having the same
horizontal co-ordinate as the horizontal co-ordinate recorded in
the computer system for a desired container; wherein the lifting
device is used to grip and hoist a top most container from the
stack, wherein the top most container that is not the desired
container is moved to a temporary position, wherein the lifting
device continues to move containers from the stack to temporary
positions until the gripping device grips the desired container,
wherein the lifting device is used to move the desired container to
a predetermined location, wherein the containers moved to temporary
positions are returned back to the stack so that their relative
order is retained, and wherein the desired container is returned to
a top of a stack; wherein an inert atmosphere is introduced into
the store.
Description
The invention concerns a method for organising the flow of goods
for a horizontally layered and deep-stacked stock of goods with
heterogeneous units, together with equipment for transfer and
continuous registration of standardised containers used in the
implementation of the invention.
In a trade organisation which purchases a multiplicity of units of
heterogeneous form, size and weight for storage and sells different
types and numbers of units from this store to customers, a
methodical organisation of the location of the units in the store
is required in order to facilitate the flow of goods.
This is necessary in order to be able to keep a stock adapted to
sales, so that the number of the individual units in the stock is
adapted to suit the expected sales.
Furthermore, it is desirable that the goods should be placed within
physically easy access in order to facilitate selection, and so
that rolling of the stock can be implemented.
Some stores collect the most sold goods in groups near packing
tables and the like in order to reduce internal movement.
With the steady increase in the use of data technology each
individual item is monitored, with the result that the physical
location will be determined and altered with every new consignment
which is purchased.
Moreover, each individual unit can be marked with bar codes which
are read mechanically for retrieval and checking, both during
dispatch and inventory and during the customer's receipt check.
Retrieval is normally conducted by staff moving through the store's
network of access passageways with, e.g., trucks or collecting
vehicles. On the basis of selection lists, based on customer
orders, and which are edited according to the position of the
different units in the store, the units are then collected which
form part of the individual order for packing and dispatch.
Various forms of automation of such stores, especially for
retrieval of units from such a store, are previously known. U.S.
Pat. No. 5,147,176 discloses such an automated storage system where
units are given a random location, and where a computer program
keeps continuous track of the position of the individual units.
This system further comprises storage shelves where the stored
units are placed in boxes. Between the storage shelves there are
access passages, and cranes or hoist devices transfer the storage
boxes to vehicles which transport them to a packing station or the
like.
Another example is described in EP 767 113, which discloses a robot
system for locating or removing units to and from a store. The
units are stacked vertically, and the robot has a gripping device
which can lift units vertically to remove them from the stack.
U.S. Pat. No. 5,340,262 describes a data based storage system which
utilizes bar code marking of ingoing goods which are placed in
standard pallet storage shelves, without the goods being related to
their physical location.
EP 0 217 757 describes an automatic transfer device for goods from
a storage place to a handling place.
NO 163276 describes sorting and holding store equipment for goods
which are continuously coming from production in a bakery and which
have to be packed in boxes according to individual customer orders,
standard boxes being sequentially transferred from each packing
station via customer stations to delivery stations.
Production and trading companies often have substantial storage
space requirements, and it is essential to be able to make the most
effective use possible of available space. The object of the
present invention is to provide a utilization of space which far
surpasses that which is achieved according to the previously known
solutions, both with regard to exploitation of floor area and
vertical stacking. Furthermore it is in an object to provide a
highly effective facility for access to stored goods together with
rolling of stored goods.
An organisation's storage requirements are closely associated with
the requirements for accessibility. Direct physical access to the
individual and oldest unit in stock is necessary and crucial for an
effective handling and rolling of the units in the stock, and this
normally has to be considered when introducing new units and, for
example, selection when dispatching orders. Heterogeneous units
cannot normally be deep-stacked, i.e. stacked on top of one another
or close to one another in the same shelf or on the same pallet.
Sufficient space must therefore be allocated in the individual
shelf to the number of units which will be present when the store
is full. If maximum stock requires space for a pallet with, e.g.,
48 units of a given unit-which, for example, may correspond to one
month's sale- and order estimates are based on the assumption that
new goods will arrive, e.g., ten days before an empty or sold-out
situation arises, together with the fact that a purchase unit is a
whole pallet, two pallet places must be allocated in the store.
Other factors which create space requirements are the staffs need
for physical access to the individual and first-incoming item.
Through-going access passageways must be laid out for trucks,
parcel trolleys and the like, and these often also have to be
allowed two-way traffic, which more than doubles the width of the
access ways.
Calculations of actual volume utilization for modern wholesale
stores where the staff require access to the stored units show a
utilization factor of only 15-20%.
When developing a traditional store of this kind, only raw goods
producers and some industrial stores with a small number of types
of goods and relatively few but major deliveries to a small number
of customers can afford to deep-stack, i.e. to stack homogeneous
articles on top of one another and close to one another in a
collective stack. A store of this kind provides a greater
utilization factor, but no access to the individual item.
The necessary requirement for stock organisation and the
above-mentioned and further objects are achieved by means of a
method which is characterized by what is stated in the claims.
A detailed description will now be given of the present invention
with reference to the appended drawings.
FIG. 1 shows a possible layout for a store which employs the
present invention.
FIG. 2 and FIG. 2a are a side view of a part of a store as
illustrated in FIG. 1, with a possible design of a lifting
device.
FIG. 3 shows a container for stored units together with a frame for
control of such containers, all viewed from above.
FIG. 4 shows the possible division of a container as illustrated in
FIG. 3 into several compartments.
FIG. 5 illustrates a hoist claw board for gripping and lifting
containers like that illustrated in FIG. 3.
FIG. 6 illustrates a possible embodiment of a packing station for
units which are removed from a store which employs the present
invention.
FIG. 7 illustrates a detail of the packing station in FIG. 6.
The present invention for organisation of goods flow for a stock of
goods of heterogeneous units is based, as shown in the example in
FIG. 1, on a thoroughly compact assembly of standardised containers
in a vertical framework. The various stored units are placed in
these standardised containers.
A container's standard dimensions for a given store is calculated
on the basis of the individual units' maximum size, and the
containers can be sectioned as illustrated in FIG. 4, by dividing
the container into several compartments by means of one or more
longitudinal or transverse partitions.
An essential condition will be that the various units which have to
be placed in the store do not vary too much in size. As a practical
example, reference may be made to a store for electronic components
or the like. In this case it will be possible to include 99% of an
assortment of approximately 50,000 variants distributed between
12,000 containers which are 70 cm long, 40 cm wide and 25 cm
high.
In order for such a stock to be contained in a traditional store in
a satisfactory manner with regard to accessibility and operating
efficiency, there is an estimated requirement for 4800 m.sup.2 of
storage surface for fitting out with shelves and access
passageways.
By employing the present invention a storage area of 420 m.sup.2
will cover the same requirement. With 60 containers in length, 25
containers in width and 8 containers in height, the required 12,000
containers can be placed in a store with a floor surface of 42
m.times.10 m, and stacked in 2 m heights. (60.times.0.7 m=42 m,
25.times.0.4 m=10 m, 8.times.0.25 m=2 m). This gives a total volume
of 820 m.sup.3.
In this example the store is served from seven packing stations,
six receiver stations and with up to four shipping stations.
The above example, therefore, is illustrated in FIG. 1, while FIG.
2 illustrates the store viewed from the side. In FIG. 2 there is
also shown a possible design of a lifting device 5 together with a
framework 6 which separates the respective stacks of containers
from one another, thus giving a highly compact storage of units.
The features which ensure an effective access to the stored goods
will now be described.
The lifting devices 5 may be composed of travelling cranes,
carriages which move on a rail system on top of the store and which
are equipped with crane devices, or any form of crane which
provides direct access to the individual stacks in the store from
the top. The practical design of the lifting devices 5 is not a
part of this invention and as an embodiment we have chosen to
employ a crane device.
We now refer to FIG. 3. All the containers 1 are of the same design
and dimensions, preferably in the form of a parallelepiped. The
containers 1 will normally be designed without a lid and with a
number of grooves 9 for insertion and attachment of a gripping
device. Such a gripping device is illustrated in FIG. 5. The
containers may advantageously be equipped with slide-forming
vertical grooves on their four outer vertical sides in order to
reduce the contact surface against the vertical framework 6 and
thereby the friction, when they are brought into vertical movement
up and out of engagement with the framework 6.
As illustrated in FIG. 4 the containers 1 may be sectioned by a
number of longitudinal or transverse partitions, thus forming a
plurality of compartments. This will prevent units which are stored
in such small amounts that they do not require a whole container
from taking up an unnecessary amount of space.
The containers are transferred by bringing a lifting device 5 which
includes a gripping device 3 into a position where it has access to
a stack of containers from the top.
A possible design of the gripping device 3 is indicated in FIG. 5.
It is in the form of a board with at least two gripping fingers 3'
which can engage with the container 1. When a gripping device of
this design is in engagement with a container, it will form a lid
which prevents the units which are stored in the container from
falling out during transfer.
In order to gain access to a given container 1 in the stack, the
containers are lifted out from the top one by one, placed in
temporary positions, for example on top of other stacks in the
immediate vicinity, until the desired container has been lifted out
of the stack. The desired container is placed temporarily in the
same manner as the containers which were placed above it, while
these other containers are replaced in the store, preferably in the
same stack and so that they are in the same order in relation to
one another. The desired container 1 is then conveyed by the
lifting device 5 from its temporary position out of the store, for
example to a packing station 7. A possible design of such a packing
station is illustrated in the FIGS. 6 and 7.
After the units concerned have been removed from the container 1,
it is returned to the store by one of the lifting devices 5.
Each individual container 5 and each individual compartment 4 in
each container is given a reference number. This reference number
is used by a computer system to keep track of the location of each
container 1 at any given time, and in which compartment in which
container a given unit is located at any time. Every time a
container 1 is brought out of the store, this is recorded in the
computer system. Each container 1 will therefore always be recorded
as being located in a given position in the actual store, in a
given intermediate storage station, in a given lifting device 5 or
at a given packing station 7. If the system also comprises
receiving stations and shipping stations, it will also be possible
for such positions to be recorded by the computer system. In short,
each localisation of each container at any time will be defined and
recorded in the computer system. In the actual store such a
position will comprise horizontal co-ordinates and vertical height
in the framework 6.
When a container 1 is placed into the store, either after
replenishment of units which are added to the store or when the
container is returned from a packing station 7, it may be placed
anywhere in the store. The position will be recorded in the
computer system, and the container can therefore be placed in the
first available vacant space.
In most stores which include a plurality of different stored units,
some units will be sold more often than others. It is therefore
desirable to place containers which contain units which are often
in demand near the top of a given stack, and preferably also near
the packing stations 7. This will reduce the retrieval time for the
store in general.
This will be performed automatically by means of the method which
is described above, the containers which are often retrieved being
placed on the top of a stack when they are returned, while the
containers which are seldom retrieved will sink to the bottom of
the stack every time a lower-lying container is removed and
returned to the top of the stack.
By considering the example which has already been discussed, where
around 80% of the sales stands to the account of 20% of the number
of variants, it is shown to be desirable that these most sold
variants should be located in or near the top layer at any time in
order to reduce the retrieval time.
Data simulation performed through three months of the orders shows
that in a horizontal 9-layer store, dispatches on this basis will
be conducted as follows:
33% from the stack surface's top layer, 14% from the second layer
and 11% from the third layer, or altogether 58% from the three top
layers. Since orders which come in in the course of a day can be
systematised into an envisaged total order, a rearrangement of the
retrieval of the store's containers can be carried out during the
night, with the result that all the containers required for the
next day's dispatch are brought up to the top, or the second top
layer, thus enabling the transfer of containers to the packing
station to be performed at maximum speed.
Ingoing goods to the store are filled in separate, new chambers 4
in a container 1, with the result that each individual ingoing
consignment according to,the list of contents is always equipped
with the supplier's receipt number as identification. Thus the same
type of article, but with a different receipt date, can be found in
several chambers 4.
Consecutive dispatches from the store entail a countdown total of
the individual chamber contents, and a check is made of the final
sale as a chamber is emptied.
The individual item is marked with a bar code for a separate final
check during dispatch and invoicing, and in order to facilitate the
customer's receipt check.
Interesting safety details are built into a system of this kind as
described: No container will disappear out of the system. They
always have to be returned. It will only be possible to remove a
container when there is an existing order. A highly concentrated
and homogeneous path for the container's travel from storage stack
to picking station will provide a very short retrieval time without
travelling staff. Container transfer takes place in a built-in
store and is therefore quiet and completely screened, thus
eliminating clamping damage. Audits of the stock are made possible
by means of separate test program runs.
An inert atmosphere, e.g. completely dry air or nitrogen, may be
introduced into the store in order to prevent corrosion. This will
be possible since the actual storage space can be kept to a minimum
size, i.e. the space is filled to the maximum extent with the
actual stock with associated equipment, and since it is not
necessary for the store staff to have physical access to the store.
The extent of the air volume is therefore relatively small.
The invention is not limited to the illustrated embodiment, and
many modifications are possible within the scope of the invention.
Other types of gripping and lifting devices, for example, may
therefore be employed than those which are illustrated, such as
carriages on rails instead of crane devices.
* * * * *